1. Field of the Invention
The present invention relates to bicycle training technology and more particularly, to a bicycle trainer, which allows change of the position of the damper unit.
2. Description of the Related Art
In order for bicycle riders to exercise cycling without being affected by weather or the environment, the most common way is to set up the bike on a bicycle trainer, enabling the bike to be pedaled indoors to achieve a training effect similar to riding a bike outdoors.
A conventional bicycle trainer, as illustrated in U.S. Pat. No. 6,945,916 (hereinafter called as Patent 916), mainly comprises a U-shaped frame 2 and two legs 3. The legs 3 can be extended out of the bottom side of the U-shaped frame 2 to allow the bicycle trainer to be positioned on the floor. A rear wheel 9 of a bicycle 8 is held in place between two side bars of the U-shaped frame 2, and kept in contact with an impeller unit 100 that provides a damping resistance to achieve training effects. Further, the U-shaped frame 2 and the legs 3 can be folded up to allow the bicycle trainer to be easily stored.
Further, U.S. Pat. No. 6,780,143 (hereinafter called as Patent 143) discloses another design of bicycle trainer, wherein first and second frame members 18, 20 are pivotally connected to each other so that when the second frame member 20 is positioned on the floor, the first frame member 18 can be moved to an operative extended “up” position with respect to the second frame member 20, allowing a rear wheel 38 of a bicycle to be placed between two arcuate end portions 36 of the first frame member 18. When a user rides the bicycle, the body weight of the user and the weight of the bicycle itself can force the wheel-rotating unit 44 and the rear wheel 38 into engagement with each other for cycling exercises.
The impeller unit 100 or wheel-rotating unit 44 used in the aforesaid Patent 916, 143 or other similar trainer for imparting a damping resistance is fixedly mounted in one lateral side of the trainer. When the U-shaped frame or the first and second frame members are collapsed, the impeller unit 100 or wheel-rotating unit 44 is still kept projecting out of the framework, and thus the trainer storage space must be relatively increased or adjusted for smooth accommodation of the collapsed bicycle trainer.
Further, the impeller unit 100 or wheel-rotating unit 44 uses a heavy wheel or magnetoresistive component to impart a damping resistance. The arrangement of this heavy wheel or magnetoresistive component will shift the center of gravity away from the structural center of the framework of the trainer. When moving the trainer, the applied force cannot be evenly distributed through the framework of the trainer, causing the user unable to carry the trainer stably and safely.